ABSTRACT A 9 month follow-up pilot study was performed in a 52-schoolchildren cohort at Santo Tomás in Iquitos, Peru. Their nutritional status was determined at the beginning and at the end of the study, as well as the presence of malaria. 9,6% children were underweight according to their age, 32,7% were smaller than what was expected for their age, 61,9% had low serum retinol concentrations and 7,7 had a body mass index (BMI) below the 5 th percentile. The parameters measured did not have significant variations when comparing initial and final measurements. The small height found was associated with the frequency of malaria (RR: 5,49, p= 0,032). This variable may be an indicator for deficient living conditions; which, in turn, favor malaria transmission.